Fawcett's longtime companion, Ryan O'Neal, presented the swimsuit and other items to the Smithsonian's National Museum of American History in Washington. O'Neal said Fawcett, who died in 2009 after battling anal cancer for several years, always intended to give the suit to the museum.

"They asked her years ago for the bathing suit," he said. "So it was always in her plan."

Fawcett wore the bathing suit for a photo shoot shortly before her debut on "Charlie's Angels" in 1976. The resulting poster sold millions of copies and became the best selling poster of all time, according to Smithsonian curator Dwight Bowers. Bowers compared the poster to World War II pinups of Betty Grable and Rita Hayworth, saying it became a symbol of the 1970s era.

Though fans know the bathing suit as red, it is actually a burnt orange color, possibly due to fading. Before it was donated to the museum, Fawcett framed it herself, and it was stored at a Los Angeles warehouse, O'Neal said.

Nels Van Patten, Fawcett's friend and tennis coach who was with her during the bathing suit shoot, said Wednesday she did her own hair and makeup for the pictures and didn't have a mirror. She also squeezed a lemon in her hair to get natural highlights, he said.

Also donated to the Smithsonian were Fawcett's book of scripts for the first season of "Charlie's Angels," a 1977 Farrah Fawcett doll and a "Farrah's Glamour Center" styling kit for creating her signature hairdo. The items will be part of the museum's popular culture history collection and will go on display this summer.

Fawcett's friends and family at the museum Wednesday for the donation included Fawcett's son with O'Neal, Redmond O'Neal, and O'Neal's daughter, Tatum O'Neal.

O'Neal, who became choked up during the ceremony, said later he feels Fawcett's presence every day.